Rather than being representations of a single graphic community at one particular time or place, Zhuang traditional manuscripts often show signs of internal dialect variation, as well readings derived from different historical strata of Chinese. Readings from different historical strata are discussed at some length in the author’s recent Mapping the Old Zhuang Character Script (Brill, 2013) and ‘A Layer of Old Chinese Readings in Traditional Zhuang Manuscripts’ (BMFEA 2015). In this article, I propose to look specifically at internal dialect variation. By internal dialect variation I mean that the characters or vernacular graphs used to represent the words in the recitation of a text show signs of having come from other localities and other dialects. I demonstrate that this phenomenon is related to the migration of Zhuang populations and social strata, as well as the circulation of texts, and can often be shown to correlate with known historical events which precipitated the movement of peoples. Furthermore, traditional texts provide evidence of hitherto unsuspected population movements, both upstream and downstream and further afield. I use a specific text as an example here: the Hanvueng scripture, for which Professor Meng Yuanyao and I have recently published a critical edition (Hanvueng: The Goose King and the Ancestral King, Brill, 2015). The theoretical implication of this discussion is that the internal analysis of vernacular texts can be used as a tool for reconstructing the history of Zhuang communities.